| Term | Definition |
| apse | a semicircular recess at the east end of a Christian church |
| gallery | second story of an aisle or ambulatory |
| iconostasis | a screen holding many images that serves as a partition between the sanctuary and the main body of the church |
| narthex | porch, or vestibule, of a church |
| pendentive | one of four concave triangular pieces of masonry used to support a dome |
| squinch | architectural elements used as a transition from a square to a polygonal or circular base for a dome |
| exarch | a Byzantine governor |
| theocrat | ruler with combined temporal and spiritual authority |
| Constantinople | formerly Byzantium |
| Procopius | historian during Justinian's reign |
| refectory | dining hall |
| inconoclasm | destruction of religious images |
| Belisarius | general who conquered Ravenna |
| icon | holy image |
| Basil I | founder of Macedonian dynasty |
| sakkos | tunic |
| Monophysite heresy | denial of duality of Christ's nature |
| paten | large golden bowl |
| Andrei Rublyev | Russian fifteenth-century artist |
| Justinian | emperor who conquered Ravenna |